Four muggers in Detroit were surprised when the man they assaulted pulled out a gun and shot at them, leaving one robber in serious condition.

Police say the suspects mugged an off-duty security guard who was on his way home, near a gas station on the city's west side. They hit him in the head with a baton when he didn't hand over his things quickly enough.

That's when the man, who's licensed to carry a concealed weapon, shot at his attackers.

One of the suspects, a 21-year-old, was struck and remains in serious condition at a nearby hospital while under arrest. The other three criminals, who all looked to be in their 20s, took off.

Watch the report from Fox 2 Detroit above.

Last summer, the Detroit police chief told Fox News that legal gun ownership was increasing in the city after he called on law-abiding citizens to consider buying a firearm and taking the necessary safety courses.

He said that crime numbers had dropped and he believed the spike in legal gun ownership was a contributing factor.

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